numpy.left_shift() in Python
numpy.left_shift() function is used to Shift the bits of an integer to the left.
The bits are shifted to the left by appending arr2 0s(zeroes) at the right of arr1. Since the internal representation of numbers is in binary format, this operation is equivalent to multiplying arr1 by 2**arr2. For example, if the number is 5 and we want to 2 bit left shift then after left shift 2 bit the result will be 5*(2^2) = 20
Attention geek! Strengthen your foundations with the Python Programming Foundation Course and learn the basics.
To begin with, your interview preparations Enhance your Data Structures concepts with the Python DS Course. And to begin with your Machine Learning Journey, join the Machine Learning - Basic Level Course
Syntax : numpy.left_shift(arr1, arr2, /, out=None, *, where=True, casting=’same_kind’, order=’K’, dtype=None, ufunc ‘left_shift’)
Parameters :
arr1 : array_like of integer type
arr2 : array_like of integer type
Number of zeros to append to arr1.The value of arr2 should be positive integer.out : [ndarray, optional] A location into which the result is stored.
-> If provided, it must have a shape that the inputs broadcast to.
-> If not provided or None, a freshly-allocated array is returned.**kwargs : allows you to pass keyword variable length of argument to a function. It is used when we want to handle named argument in a function.
where : [array_like, optional]True value means to calculate the universal functions(ufunc) at that position, False value means to leave the value in the output alone.
Return : array of integer type.
Return arr1 with bits shifted arr2 times to the left. This is a scalar if both arr1 and arr2 are scalars.
Code #1 : Working
# Python program explaining# left_shift() function import numpy as geekin_num = 5bit_shift = 2 print ("Input number : ", in_num)print ("Number of bit shift : ", bit_shift ) out_num = geek.left_shift(in_num, bit_shift) print ("After left shifting 2 bit : ", out_num) |
Output :
Input number : 5 Number of bit shift : 2 After left shifting 2 bit : 20
Code #2 :
# Python program explaining# left_shift() function import numpy as geek in_arr = [2, 8, 15]bit_shift =[3, 4, 5] print ("Input array : ", in_arr) print ("Number of bit shift : ", bit_shift) out_arr = geek.left_shift(in_arr, bit_shift) print ("Output array after left shifting: ", out_arr) |
Output :
Input array : [2, 8, 15] Number of bit shift : [3, 4, 5] Output array after left shifting: [ 16 128 480]

Formed in 2009, the Archive Team (not to be confused with the archive.org Archive-It Team) is a rogue archivist collective dedicated to saving copies of rapidly dying or deleted websites for the sake of history and digital heritage. The group is 100% composed of volunteers and interested parties, and has expanded into a large amount of related projects for saving online and digital history.
